(a) Field of the Invention
The present invention relates to a multimedia search method for searching multimedia objects using color histogram, and in particular, to a multimedia search method capable of accelerating accurate and efficient multimedia object search using improved multimedia features extraction, and multimedia feature data structure therefor.
(b) Description of the Related Art
Recently, content-based multimedia search technologies were reported and various search engines are developed in image search field.
Well known are methods for searching images using entire color histogram, local color information, and texture information. Especially, the color- and texture-information weighted image retrieval technologies are reported.
Most of these conventional technologies use various information such as color and texture for content-based retrieval, particularly a color histogram as the most important information.
A color histogram is a representation of a random distribution of colors and the number of bins that are comprised in the histogram depends on a color quantization level.
A value of the bin is represented by a floating-point number and similarity of two images is determined by a distance between the two histograms of the images. Thus, the floating-point number calculation requires a much memory space over the net value of the bin.
Although the distance computation is not difficult and guarantee that relatively similar images are identified, this may require an enormous amount of time and computing resources for repeatedly comparing lots of image features when browsing lots of images.
Also, the color histogram is considered just as a color distribution of an image such that it is difficult to expect a considerable search performance in itself.
While image retrievals are performed using the same color histogram, the result can differ from each other according to similarity measurements and each bin of the color histogram can have a little difference such that an improved retrieval technology can be conceived by using these characteristics.
The present invention has been made in an effort to solve the above problems of the prior art.
It is an object of the present invention to provide a multimedia retrieval method and a multimedia feature structure capable of accelerating accurate and efficient multimedia object search by adopting various meaning reflection level according to each bin value of the color histogram.
To achieve the above object, in the present invention, the color groups are classified into the solid, neutral, and gray levels, and the binarization standard point is determined at each color group such that the color distribution can be effectively represented in the binary histogram, resulting in improving the retrieval performance of binary color histogram which is a shortcoming in the conventional binary histograms in addition to remaining the high efficiency of the binary color histogram.